Rachel took over-the-counter medication for chronic back pain and was also given prescription-only drugs by her parents

But unbeknown to doctors, the teenager's father Colin and mother Joann were also repeatedly giving their daughter his prescription-only medication which included morphine tablets and another powerful painkiller Tramadol.

After Rachel was found dead in bed by her mother at the family home in Stalybridge, Greater Manchester in September last year, blood tests showed she died from morphine toxicity with a level in her system more than TWELVE times the recognised fatal dose.

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Joann and Colin Murphy admitted giving their tragic daughter drugs that killed her

"It was only when she had a really bad fit and really knocked herself about. I know I shouldn't have done it but I did. ''

Earlier the inquest was told Rachel who was studying for her GCSEs at Copley High School in Stalybridge had a history of seizures dating back to 2007 and also suffered from Scoliosis and the arthritic condition Ankylosing Spondylitis.

She was diagnosed with epilepsy in 2013 and her condition led to being off school for long periods at a time.

Healthcare professionals and family support workers held a series of meetings during which officials learnt Rachel also suffering from ''stress attacks'' and ''low moods'' and had been sleeping for long periods at a time. She also scratched herself and pulled her hair.

But there were disagreements between the professionals as to how best treat Rachel and decisions about best to treat her came to a ''dead end.''

Mr Murphy - who had been prescribed Tramadol and morphine for his severe arthritis - told the inquest: ''She was having three different types of seizures, possibly four.

Rachel missed school repeatedly due to her fits which would also leave her asleep for long periods of time

''She wanted to go to school.

''She liked school, she was doing very well at it even in the subjects that she didn't like.

When asked about his medicine Mr Murphy, 55, said he kept the drugs in ''a top drawer with all sorts of stuff'' but he said he first started giving his daughter Tramadol tablets before switching to morphine when it was prescribed to him by his doctor.

He added: ''When she had a fit she would fall to her knees, and then on her chest so she would complain that it was sore or painful. It was the only painkillers I had available at the house at that time. It was given when we were out of over the counter painkillers.''

Joann told hearing that she believed she was helping her daughter Rachel by giving her drugs she was not prescribed

''To be honest I suspected the painkillers weren't working anyway and I stopped giving her the tramadol. I thought something slightly stronger might.''

He said he himself had been put on morphine for a month in January 2015 but came off it when it made him sleep too much. He said he started giving his daughter er morphine tablets the following April but denied giving her morphine for a seizure she suffered the day before her death.

Toxicologist Julie Evans said that a ''therapeutic'' level of Tramadol and the anti epilepsy drug Keppra was found in Rachel’s blood.

Rachel’s parents were quizzed by police under caution but no action was taken

"But she the morphine level in the teenager's system was 633 microgrammes per litre, with 50mg being the maximum for a 'naïve user' before it became fatal

Miss Evans said: "It is likely that in the couple of days leading up to her death Rachel had taken the drug more than once. It is likely she took more than 15 tablets over the two days. It could obviously be longer."

Det Insp David Loughlin of Greater Manchester Police confirmed officers spoke to Mr and Mrs Murphy after reading the toxicology report. He added: ''Mum and dad agreed to go down to the station.

''They were interviewed under caution and spoke to the police with regards to the drugs that they had been giving their daughter. Mum admitted that she had given her Tramadol and dad that he had given her Tramadol and morphine.''

The hearing continues.

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